The invention relates to an rpm regulator for fuel injection pumps for use in internal combustion engines of the type which includes at least one intermediate control lever, one arm of which is engaged by a primary rpm-dependent governor mechanism acting in opposition to the arbitrarily variable force of a regulator spring and whose other arm is coupled to the fuel quantity setting member of the fuel injection pump. A stop, which is adjustable against the force of a spring by rpm-dependent means, limits the path of the fuel quantity setting member in the direction of increasing the delivered fuel quantity and determines the maximum fuel quantity supplied to the engine. The rpm-dependent means which sets the stop is actuated by control fluid whose pressure increases with increasing rpm and the adjustment of the stop is independent of the state of the primary rpm-dependent governor mechanism.
In the known rpm regulator of this type, the rpm-dependent fuel pump pressure sets a plunger provided with a cam plate against the force of an adapter spring, and one arm of a bell crank lever serves as a stop for the above mentioned intermediate lever, whereas the other arm of the bell crank lever follows the track of the cam plate. The construction of such a cam plate is relatively expensive however, and, furthermore, the bell crank lever and the control spring cause relatively high forces to be transmitted to the plunger.
As examples of known prior art devices owned by the assignee of this application, see Eheim, U.S. Pat. No. 3,635,603, issued Jan. 18, 1972 and also Eheim, U.S. Pat. No. 3,638,631, issued Feb. 1, 1972.